SMS Archiver

SMS Archiver
is a PHP script to convert from the smi/smo format used on Siemens phones to archive SMS messages. It works for the Siemens S55 and may well work on others.
The format used is similar to the SMS specification in that the text is encoded in the PDU format and the phone numbers and date conform.

VCalOne

VCalOne
converts vCalendar version 2 data to a limited subset of
vCal version 1. VCalOne can convert a calendar saved from korganizer to a
format suitable for uploading to a Nokia 6820 cell phone.
license: GNU General Public License (GPL)

Handy

Handy
is a small console program to convert the output of Lotus Notes client version 5.x into a vCal Version 2.0 file and/or sends the appointments to a cellphone of type SIEMENS S45 and maybe S35 also.

Mobile Bookshelf

Mobile Bookshelf
converts text file(s) to a MIDlet (a Java program
that can be run on a mobile phone), making it possible to read your
favourite books on your handset.
license: GNU General Public License (GPL)

RTTTL2WAV

RTTL2WAV
converts a RTTTL-formatted mobile phone ringing tone to a WAV
file. The output of this program can also be copied to stdout as a raw PCM
data (linear 44.1kHz signed 16bit integers). It also includes a shell
script which allows you to listen ringing tones directly with your sound
card.
license: GNU General Public License (GPL)

Nokryptia - Linux MP3 to LSE Conversion Tool

Nokryptia is a program to convert music files like MP3 to LSE format, to work on a Nokia 5510
cell phone. The application
itself does not know anything about USB, therefore you will need to recompile
the kernel. The advantage of this aproach is that you can use your mobile as a
"large" disk of 64MB. The utility also does not do any encryption, it uses
in fact a bug in the encryption algorithm. Therefore, no actual encryption is
done, which makes the program very fast in comparision to the official
Microsoft-Windows program from NOKIA.

Converting 3GP video files HOWTO

Converting 3GP video files HOWTO:
The Nokia phone generates 3GPP video files and the main challenge here is to convert such files into something that would play in any computer without requiring any special codecs or software. Even though Nokia distributes a codec for free and Quicktime now supports 3GPP, you may want to be able to painlessly play videos on any computer, e.g. on a Linux box, you can only play 3GPP videos with Realplayer 10 as MPlayer lacks audio support for this codec.

AMR (Adaptive Multi-Rate) Converter

Ringtone Tools

Ringtone Tools
is a program for creating custom ringtones and graphical logos for mobile phones. I've tested this program myself on Nokia and Kyocera phones (including the Kyocera 6035 PDA Smartphone). I also include support for my other types of phones including Ericsson, Sony/Ericsson, Motorola, Siemens, Samsung, Handspring Treo phones, and phones that support EMS, but since I have no way to test these, I rely on the words of others who say they work. I plan on adding support for other phones as soon as I get sponsors and testers. Ringtone Tools can also be used to convert between many file formats, including WBMP which can be used on WAP .wml web pages and .ico which can be used to make favicon.ico's.

Media-Convert

Media-Convert
is a free online service that can be used to turn ANY audio file into just about ANY
ringtone format - and it's all online so it's OS independent.

3gpwiz - 3gp movie wizard

3gpwiz
converts any movie format to a 3gp movie, suitable for watching on a mobile phone.